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One of the benefits of the combined heat and power (CHP) systems is reducing greenhouse gases (GHG) in the national level. These systems are installed in the close vicinity of local communities and their pollution can directly affect the local environment. This paper studies the adverse environmental effects of a 2 MW gas-burning CHP (GB-CHP) system in a residential community in Mashhad, Iran. We compare the amount of C O 2 and N O x emissions from the GB-CHP with the conventional choice of supplying electricity from the central power plants and heat from the locally installed boilers. The results show that the GB-CHP system increases local C O 2 and N O x emissions by approximately two and six times, respectively. The N O x emission is increased from 3.1 tonnes to 18.7 tonnes. The C O 2 emission increases from 3623 tonnes to 7238 tonnes. Furthermore, we use Gaussian Dispersion model to estimate the concentration of these emissions in the local area using the weather conditions of the most polluted times of the previous year. The results show that for a 3-meter stack, the maximum concentration of C O 2 and N O x are 14.8 m g / m 3 and 38.1 μ g / m 3 , respectively. Our analysis shows that increasing the height of the GB-CHP stack from 3 meters to 10 meters reduces the concentration by 40%. [ABSTRACT FROM AUTHOR]

This paper presents an emission inventory (EI) for biomass open burning (OB) sources including forest, agro-residue and municipal solid waste (MSW) in Indonesia for year 2007. The EI covered toxic air pollutants and greenhouse gases (GHGs) and was presented as annual and monthly average for every district, and further on a grid of 0.25° × 0.25°. A rigorous analysis of activity data and emission factor ranges was done to produce the low, best and high emission estimates for each species. Development of EI methodology for MSW OB which, to our best knowledge, has not been presented in detail in the literature was a focus of this paper. The best estimates of biomass OB emission of toxic air pollutants for the country, in Gg, were: 9.6 SO2; 98 NOx; 7411 CO; 335 NMVOC; 162 NH3; 439 PM10; 357 PM2.5; 24 BC; and 147 OC. The best emission estimates of GHGs, in Gg, were: 401 CH4, 57,247 CO2; and 3.6 N2O. The low and high values of the emission estimates for different species were found to range from −86% to +260% of the corresponding best estimates. Crop residue OB contributed more than 80% of the total biomass OB emissions, followed by forest fire of 2–12% (not including peat soil fire emission) and MSW (1–8%). An inter-annual active fires count for Indonesia showed relatively low values in 2007 which may be attributed to the high rainfall intensity under the influence of La Niña climate pattern in the year. Total estimated net climate forcing from OB in Indonesia was 110 (20 year horizon) and 73 (100 year horizon) Tg CO2 equivalents which is around 0.9–1.1% of that reported for the global biomass OB for both time horizons. The spatial distribution showed higher emissions in large urban areas in Java and Sumatra Island, while the monthly emissions indicated higher values during the dry months of August–October. [ABSTRACT FROM AUTHOR]

In developing countries like India, urban solid waste (SW) generation is increasing enormously and most of the SWs are disposed off by land filling in low-lying areas, resulting into generation of large quantities of biogas. Methane, the major constituent gas is known to cause global warming due to green house gas (GHG) effect. There is a need to study the ever-increasing contribution of SW to the global GHG effect. To assess the impacts, estimation of GHG emission is must and to avoid misguidance by these emission-data, qualitative assessment of the estimated GHG is a must. In this paper, methane emission is estimated for a particular landfill site, using default methodology and modified triangular methodology. Total methane generation is same for both theoretical methodologies, but the modified triangular method has an upper hand as it provides a time-dependent emission profile that reflects the true pattern of the degradation process. To check the quality of calculated emission-data, extensive sampling is carried out for different seasons in a year. Field results show a different trend as compared to theoretical results, this compels for logical thinking. Each methane emission-data is backed up by the uncertainty associated with it, this further strengthens the quality check of these data. Uncertainty calculation is done using Monte Carlo simulation technique, recommended in IPCC Guideline. In the due course of qualitative assessment of methane emission-data, many site-specific sensitive parameters are discovered and are briefly discussed in this paper. [Copyright &y& Elsevier]

The change of O 2 content in soil caused by aerated irrigation (AI) must inevitably affect the production and emissions of CO 2 and N 2 O from soils. This paper described in-situ observation of CO 2 and N 2 O emissions from AI soils with static chamber-GC technique, in order to reveal the effects of AI on CO 2 and N 2 O emissions from soils of greenhouse tomato fields in autumn-winter season. CO 2 and N 2 O emissions from AI soils mainly concentrated in the blooming and fruit setting period compared to other periods. AI increased cumulative emissions of CO 2 and N 2 O by 11.8% (p = 0.394) and 10.0% (p = 0.480), respectively, compared to the control. The integrative global warming potential of CO 2 and N 2 O on a 100-year horizon for the AI treatment was 6430.60 kg ha −1 , increased by 11.7% compared with that for the control (p = 0.356). Both the emissions of CO 2 and N 2 O from AI soils had the exponential positive correlation with soil water-filled pore space (WFPS). The highest peak of CO 2 and N 2 O fluxes from AI soils was observed at 46.7% and 47.5% WFPS, with WFPS ranging from 43.3% to 51.5% and from 45.6% to 52.3% during the whole growth stage, respectively. In addition, the average yield for the AI treatment (34.52 t ha −1 ) was significantly greater (17.4%) compared with that of the control (p = 0.018). These results suggest that AI do not significantly increase the integrative greenhouse effect caused by CO 2 and N 2 O from soils of greenhouse tomato fields, but significantly increase the tomato yield. The research results provide certain theoretical foundation and scientific basis for accurately evaluating the farmland ecological effect of AI technique. [ABSTRACT FROM AUTHOR]

This paper presents airborne measurements of multiple atmospheric trace constituents including greenhouse gases (such as CO 2 , CH 4 , O 3 ) and biomass burning tracers (such as CO, CH 3 CN) downwind of an exceptionally large wildfire. In summer 2013, the Rim wildfire, ignited just west of the Yosemite National Park, California, and burned over 250,000 acres of the forest during the 2-month period (17 August to 24 October) before it was extinguished. The Rim wildfire plume was intercepted by flights carried out by the NASA Ames Alpha Jet Atmospheric eXperiment (AJAX) on 29 August and the NASA DC-8, as part of SEAC 4 RS (Studies of Emissions, Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys), on 26 and 27 August during its intense, primary burning period. AJAX revisited the wildfire on 10 September when the conditions were increasingly smoldering, with slower growth. The more extensive payload of the DC-8 helped to bridge key measurements that were not available as part of AJAX (e. g. CO). Data analyses are presented in terms of emission ratios (ER), emission factors (EF) and combustion efficiency and are compared with previous wildfire studies. ERs were 8.0 ppb CH 4 (ppm CO 2 ) −1 on 26 August, 6.5 ppb CH 4 (ppm CO 2 ) −1 on 29 August and 18.3 ppb CH 4 (ppm CO 2 ) −1 on 10 September 2013. The increase in CH 4 ER from 6.5 to 8.0 ppb CH 4 (ppm CO 2 ) −1 during the primary burning period to 18.3 ppb CH 4 (ppm CO 2 ) −1 during the fire's slower growth period likely indicates enhanced CH 4 emissions from increased smoldering combustion relative to flaming combustion. Given the magnitude of the Rim wildfire, the impacts it had on regional air quality and the limited sampling of wildfire emissions in the western United States to date, this study provides a valuable dataset to support forestry and regional air quality management, including observations of ERs of a wide number of species from the Rim wildfire. [ABSTRACT FROM AUTHOR]

Abstract: Landfills are important anthropogenic sources of methane (CH4) emission especially in fast urbanizing countries. This paper presents the CH4 emission estimations carried out using the in-situ CH4 measurements, IPCC 1996 Default methodology (DM), Modified Triangular Method (MTM) and First Order Decay (FOD) method for the three landfills currently operational in the capital city Delhi of India. The in-situ methodology has yielded the landfills specific methane emission factors (EFs). The annual average methane emission rates from three landfills namely, Ghazipur (GL), Bhalswa (BL) and Okhla (OL) are 14.6, 23.6 & 7.5 Gg y−1 by DM; 13.3, 10.6 & 7.2 Gg y−1 by the FOD; 17.0, 13.7 and 10.7 Gg y−1 by the MTM; and 4.6, 4.2 and 1.4 Gg y−1 by the in-situ measurement method respectively. The CH4 EFs have been found to be 9.7 ± 2.6, 5.5 ± 1.6 and 5.5 ± 1.7 g kg−1 of waste respectively for the GL, BL and OL landfills in Delhi. The study reveals that in-situ methodology seems to provide better representative emission estimation compared to other methods. The FOD method also yields comparable results with that of in-situ methodology in cases where good waste composition data is available. [Copyright &y& Elsevier]

Abstract: Quantifying trace gas emissions and the influence of surface exchange processes on the atmosphere is a necessary step towards the control of global greenhouse gas emissions and reliability of air quality models. This paper proposes a procedure based on the mass balance method and implemented on highly resolved aircraft data. It allows one to estimate surface exchanges on areas of several km2 and heterogeneous features exploiting the characteristics of convective boundary layer during steady state conditions that permit the estimation of emission/absorption terms as functions of advective fluxes only. A nonparametric approach is adopted and the fluxes on the surface of a virtual box surrounding the area of interest are reconstructed on the basis of scalar densities and wind vectors using Shepard functions. Two different techniques are also proposed to face lack of data on the top surface of the box. The method has been applied to experimental data coming from measurement campaigns on two different sites. It provides realistic estimates of the CO2 emission/absorption in the considered areas that are in good agreement with CO2 fluxes evaluated by Airborne Eddy Covariance and confirm the suitability of the proposed approach for the assessment of turbulent exchange of trace gases by composite landscapes. Uncertainties on the estimated emissions due to both propagation of the experimental error and interpolation have been quantified by bootstrap analysis as 6%. [Copyright &y& Elsevier]

Abstract: A decentralized emission inventories are prepared for road transport sector of India in order to design and implement suitable technologies and policies for appropriate mitigation measures. Globalization and liberalization policies of the government in 90''s have increased the number of road vehicles nearly 92.6% from 1980–1981 to 2003–2004. These vehicles mainly consume non-renewable fossil fuels, and are a major contributor of green house gases, particularly CO2 emission. This paper focuses on the statewise road transport emissions (CO2, CH4, CO, NOx, N2O, SO2, PM and HC), using region specific mass emission factors for each type of vehicles. The country level emissions (CO2, CH4, CO, NOx, N2O, SO2 and NMVOC) are calculated for railways, shipping and airway, based on fuel types. In India, transport sector emits an estimated 258.10 Tg of CO2, of which 94.5% was contributed by road transport (2003–2004). Among all the states and Union Territories, Maharashtra''s contribution is the largest, 28.85 Tg (11.8%) of CO2, followed by Tamil Nadu 26.41 Tg (10.8%), Gujarat 23.31 Tg (9.6%), Uttar Pradesh 17.42 Tg (7.1%), Rajasthan 15.17 Tg (6.22%) and, Karnataka 15.09 Tg (6.19%). These six states account for 51.8% of the CO2 emissions from road transport. [Copyright &y& Elsevier]

This paper summarizes greenhouse gas (GHG) emissions measurements obtained during several recent studies conducted by Environment Canada, Emissions Research and Measurement Division (ERMD). A variety of heavy-duty vehicles and engines operating on a range of different fuels including diesel, biodiesel, compressed natural gas (CNG), hythane (20% hydrogen, 80% CNG), and liquefied natural gas (LNG), and with different advanced aftertreatment technologies were studied by chassis dynamometer testing, engine dynamometer testing or on-road testing. Distance-based emission rates of CO2, CH4, and N2O are reported. Fuel consumption calculated by carbon balance from measured emissions is also reported. The measurement results show, for heavy-duty diesel vehicles without aftertreatment, that while CO2 emissions dominate, CH4 emissions account for between 0% and 0.11% and N2O emissions account for between 0.16% and 0.27% of the CO2-equivalent GHG emissions. Both of the aftertreatment technologies (diesel oxidation catalyst and active regeneration diesel particle filter) studied increased N2O emissions compared to engine out emissions while CH4 emissions remain essentially unchanged. No effect on tailpipe GHG emissions was found with the use of up to 20% biodiesel when the engine was equipped with an oxidation catalyst. Biodiesel use did show some reductions in tailpipe GHG emissions as compared to ULSD without aftertreatment and with the use of a diesel particle filter. Natural gas and hythane also offer decreased GHG emissions (10–20%) at the tailpipe when compared with diesel. Emission factors (gL−1 fuel) for CH4 and N2O are suggested for heavy-duty vehicles fueled with diesel-based fuels and natural gas. These emission factors are substantially lower than those recommended for use by IPCC methodologies for developing national inventories. [Copyright &y& Elsevier]

Abstract: This paper provides the trends of greenhouse gas (GHG) and local air pollutant emissions of India for 1985–2005. The GHGs covered are six Kyoto gases, namely carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), perfluorocarbons (PFCs), hydrofluorocarbons (HFCs) and sulfur hexafluoride (SF6). The local air pollutants are sulfur dioxide (SO2), nitrogen oxides (NO X ), carbon monoxide (CO) and total suspended particulates (TSP). These estimates incorporate some of the most recent scientific assessments for India. The multigas emissions have varied sectoral and fuel-based dominance, as well as regional distribution patterns. Coal consumption in power sector dominates CO2 and SO2 emissions, while power and road transport equally contribute to NO X emissions. Rice cultivation and livestock-related emissions from the agriculture sector dominate CH4 emissions, while synthetic fertilizer use in the same sector is the major source of N2O emissions. PFC emissions are dominated by C2F6 and CF4 emissions from aluminum production. The majority of HFC emissions are contributed by HFC-23, a by-product during the production of HCFC-22 that is widely used in refrigeration industry. CO emissions have dominance from biomass burning. Particulate emissions are dominated by biomass burning (residential sector), road transport and coal combustion in large plants. These varied emission patterns provide interesting policy links and disjoints, such as—which and where mitigation flexibility for the Kyoto gases, exploring co-benefits of CO2 and SO2 mitigation, and technology and development pathway dependence of emissions. The present inventory assessment is a pointer to the future emission pathways for India wherein local air pollutant and GHG emissions, although connected, may not move in synchronization and therefore would require alignment through well crafted development and environment strategies. [Copyright &y& Elsevier]